From [this discussion group post](https://groups.google.com/g/xnat_discussion/c/c1FwszBjXSY/m/iA3W2LOEAAAJ):
Another confusing (and troubling) aspect of this upgrade is that my previous Site ID string had been used as the prefix for all IDs for Subjects, Experiments, etc. these objects are now using the Site ID with a "01" appended to it, and the counters for subject, experiment, etc. are set back to 1. For instance, if my Site ID was "XnatSite", and previous Subjects were IDed as "XnatSite_S00541", new subjects have IDs such as ""XnatSite01_S00001". Note that in my Administer > Site Setup > Site Information, the Site ID is still showing as the original string (without the 01).
Unfortunately, this breaks a number of mechanisms that I have which relies on the original pattern. Is this expected behavior? Is there any way to change it back to the previous Site ID and pattern?
The ID generator is supposed to ignore the host number/node ID in single-node configurations, but the check for that wasn't added in the appropriate place, so host number is alway "01" in single-node configurations. Just checking XnatAppInfo.hasMultipleActiveNodes() and setting host number to an empty string when that's false suffices.